What hp is my mercury thunderbolt

[brummy]

Hi guys.I wonder if anyone can help me.I bought 2 engines years ago now, one was a 20hp the other i'm not sure about but it was the auxillary to the bigger one.The cowlings a bit worse for wear and you cant tell what the hp markings say.I have the feeling its either a 4 or 5hp or 7.5hp at a push.How can i find out what size it is, all i know is its a long shaft.Can a serial number tell more ? Sorry to ask but its doing me bloody head in!!!! cheers in advance

 

[Laddies]

Re: What hp is my mercury thunderbolt

3.9 and 4 HP are single cyl. engines, 6 and 7.5 have comet cast in the powerhead and that only leaves the 110 or 9.8

 

[brummy]

Re: What hp is my mercury thunderbolt

3.9 and 4 HP are single cyl. engines, 6 and 7.5 have comet cast in the powerhead and that only leaves the 110 or 9.8

Sorry to be a pain, but comet cast is what exactly ? Thanks again laddies

 

[Laddies]

Re: What hp is my mercury thunderbolt

It's cast in a pad on the starboard side of the powerhead

 

[brummy]

Re: What hp is my mercury thunderbolt

It's cast in a pad on the starboard side of the powerhead

Thanks alot laddie.